Method of depositing carbon-containing material on a surface of a substrate, structure formed using the method, and system for forming the structure

ABSTRACT

Methods and systems for filling a recess on a surface of a substrate with carbon-containing material are disclosed. Exemplary methods include forming a first carbon layer within the recess, etching a portion of the first carbon layer within the recess, and forming a second carbon layer within the recess. Structures formed using the method or system are also disclosed.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No.62/937,924, filed on Nov. 20, 2019 in the United States Patent andTrademark Office, the disclosure of which is incorporated herein in itsentirety by reference.

FIELD OF INVENTION

The present disclosure generally relates to methods of formingstructures suitable for use in the manufacture of electronic devices.More particularly, examples of the disclosure relate to methods offilling gaps with carbon-containing material during the formation ofstructures.

BACKGROUND OF THE DISCLOSURE

During the manufacture of devices, such as semiconductor devices, it isoften desirable to fill features (e.g., trenches or gaps) on the surfaceof a substrate with insulating or dielectric material. Some techniquesto fill features include the deposition of carbon-containing material.

Although use of carbon-containing material to fill features can workwell for some applications, filling features using traditionaldeposition techniques has several shortcomings, particularly as a sizeof the features to be filled decreases. For example, during depositionof carbon-containing material, voids can form within the depositedmaterial, particularly within gaps. Such voids can remain even afterreflowing the deposited material. Further, an undesirably wavy or roughtop surface of the deposited carbon-containing material can form. Theundesirably wavy or rough top surface can detrimentally affectsubsequent processing steps, such as patterning, etching, and/ordeposition steps.

As device and feature sizes continue to decrease, it becomesincreasingly difficult to apply conventional carbon-containing materialdeposition techniques to manufacturing processes. Accordingly, improvedmethods for forming structures, particularly for methods of formingstructures that include filling gaps with carbon-containing material,that mitigate void formation in the carbon-containing material and/orthat provide a smoother top surface of the carbon-containing material,are desired.

Any discussion, including discussion of problems and solutions, setforth in this section, has been included in this disclosure solely forthe purpose of providing a context for the present disclosure, andshould not be taken as an admission that any or all of the discussionwas known at the time the invention was made or otherwise constitutesprior art.

SUMMARY OF THE DISCLOSURE

Various embodiments of the present disclosure relate to methods offorming structures suitable for use in the formation of electronicdevices. While the ways in which various embodiments of the presentdisclosure address drawbacks of prior methods and structures arediscussed in more detail below, in general, exemplary embodiments of thedisclosure provide improved methods for filling features on a surface ofa substrate with carbon-containing material and/or to forming layers orfilms comprising carbon.

In accordance with various embodiments of the disclosure, methods offilling a recess on a surface of a substrate are provided. Exemplarymethods can include providing a substrate in a reaction space of areactor, the substrate comprising a surface comprising a recess; forminga first carbon layer within the recess, wherein the first carbon layercan be initially flowable; etching a portion of the first carbon layerwithin the recess; and forming a second carbon layer within the recess.The second carbon layer can also be initially flowable. Exemplarymethods can further include a step of etching a portion of the secondcarbon layer. Methods can further include forming a third (or top)carbon layer overlying the second carbon layer. The steps of forming thesecond carbon layer and etching the portion of the second carbon layercan be repeated a number of times prior to the step of forming the thirdcarbon layer. In some cases, the first carbon layer can fill the recessto at least a top surface of the substrate. In such cases, the step ofetching a portion of the first carbon layer can include etching thefirst carbon layer until a surface of the first carbon layer within therecess is below the top surface. In accordance with further examples ofthe disclosure, the second carbon layer can fill the recess to at leasta top surface of the substrate. The step of etching a portion of thesecond carbon layer can also include etching the second carbon layeruntil a surface of the second carbon layer within the recess is belowthe top surface. One or more of the carbon-containing layers can bedeposited using a cyclic deposition process, such as a plasma-enhancedcyclic deposition process. A plasma-enhanced cyclic deposition processcan include providing a dilution gas, such as argon or helium, to aremote or direct plasma unit for igniting and sustaining a plasma.Exemplary methods can further comprise a treatment step to treat one ormore of the carbon layers. A treatment step can include a plasmatreatment step—e.g., treatment with species formed from one or more ofargon, helium, nitrogen, and hydrogen. Various etching steps can beperformed using a plasma-enhanced etch process.

In accordance with yet further exemplary embodiments of the disclosure,a structure is formed, at least in part, according to a method describedherein.

In accordance with yet further exemplary embodiments of the disclosure,a system is provided for performing a method and/or for forming astructure as described herein.

These and other embodiments will become readily apparent to thoseskilled in the art from the following detailed description of certainembodiments having reference to the attached figures; the invention notbeing limited to any particular embodiment(s) disclosed.

BRIEF DESCRIPTION OF THE DRAWING FIGURES

A more complete understanding of exemplary embodiments of the presentdisclosure can be derived by referring to the detailed description andclaims when considered in connection with the following illustrativefigures.

FIG. 1 illustrates a method in accordance with exemplary embodiments ofthe disclosure.

FIG. 2 illustrates a scanning transmission electron microscopy image ofa structure including a carbon layer.

FIG. 3 schematically illustrates structures formed using a method inaccordance with examples of the disclosure.

FIG. 4 illustrates scanning transmission electron microscopy images ofstructures formed in accordance with exemplary embodiments of thedisclosure.

FIG. 5 illustrates a system in accordance with exemplary embodiments ofthe disclosure.

It will be appreciated that elements in the figures are illustrated forsimplicity and clarity and have not necessarily been drawn to scale. Forexample, the dimensions of some of the elements in the figures may beexaggerated relative to other elements to help improve understanding ofillustrated embodiments of the present disclosure.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

Although certain embodiments and examples are disclosed below, it willbe understood by those in the art that the invention extends beyond thespecifically disclosed embodiments and/or uses of the invention andobvious modifications and equivalents thereof. Thus, it is intended thatthe scope of the invention disclosed should not be limited by theparticular disclosed embodiments described below.

The present disclosure generally relates to methods of depositingmaterials, to methods of forming structures, to structures formed usingthe methods, and to systems for performing the methods and/or formingthe structures. By way of examples, the methods described herein can beused to fill features, such as gaps (e.g., trenches or vias) on asurface of a substrate with material, such as carbon-containing (e.g.,dielectric) material. The terms gap and recess can be usedinterchangeably.

To mitigate void and/or seam formation, the carbon-containing materialcan be initially flowable and flow within the gap to fill the gap fromthe bottom upward. Exemplary structures described herein can be used ina variety of applications, including, but not limited to, cell isolationin 3D cross point memory devices, self-aligned vias, dummy gates,reverse tone patterns, PC RAM isolation, cut hard mask, DRAM storagenode contact (SNC) isolation, and the like.

In this disclosure, “gas” can refer to material that is a gas at normaltemperature and pressure, a vaporized solid and/or a vaporized liquid,and may be constituted by a single gas or a mixture of gases, dependingon the context. A gas other than a process gas, i.e., a gas introducedwithout passing through a gas distribution assembly, such as ashowerhead, other gas distribution device, or the like, may be used for,e.g., sealing a reaction space, which includes a seal gas, such as arare gas. In some cases, such as in the context of deposition ofmaterial, the term “precursor” can refer to a compound that participatesin the chemical reaction that produces another compound, andparticularly to a compound that constitutes a film matrix or a mainskeleton of a film, whereas the term “reactant” can refer to a compound,in some cases other than a precursor, that activates a precursor,modifies a precursor, or catalyzes a reaction of a precursor; a reactantmay provide an element (such as O, H, N, C) to a film matrix and becomea part of the film matrix when, for example, radio frequency (RF) poweris applied. In some cases, the terms precursor and reactant can be usedinterchangeably. The term “inert gas” refers to a gas that does not takepart in a chemical reaction to an appreciable extent and/or a gas thatexcites a precursor when, for example, RF power is applied, but unlike areactant, it may not become a part of a film matrix to an appreciableextent.

As used herein, the term “substrate” can refer to any underlyingmaterial or materials that may be used to form, or upon which, a device,a circuit, or a film may be formed. A substrate can include a bulkmaterial, such as silicon (e.g., single-crystal silicon), other Group IVmaterials, such as germanium, or compound semiconductor materials, suchas GaAs, and can include one or more layers overlying or underlying thebulk material. Further, the substrate can include various features, suchas gaps (e.g., recesses or vias), lines or protrusions, such as lineshaving gaps formed therebetween, and the like formed within or on atleast a portion of a layer or bulk material of the substrate. By way ofexamples, one or more features can have a width of about 10 nm to about100 nm, a depth or height of about 30 nm to about 1000 nm, and/or anaspect ratio of about 3 to 100 or about 3 to about 20.

In some embodiments, “film” refers to a layer extending in a directionperpendicular to a thickness direction. In some embodiments, “layer”refers to a material having a certain thickness formed on a surface andcan be a synonym of a film or a non-film structure. A film or layer maybe constituted by a discrete single film or layer having certaincharacteristics or multiple films or layers, and a boundary betweenadjacent films or layers may or may not be clear and may or may not beestablished based on physical, chemical, and/or any othercharacteristics, formation processes or sequence, and/or functions orpurposes of the adjacent films or layers. The layer or film can becontinuous—or not.

As used herein, the term “carbon layer” or “carbon-containing material”can refer to a layer whose chemical formula can be represented asincluding carbon. Layers comprising carbon-containing material caninclude other elements, such as one or more of nitrogen and hydrogen.

As used herein, the term “structure” can refer to a partially orcompletely fabricated device structure. By way of examples, a structurecan include a substrate with one or more layers and/or features formedthereon.

As used herein, the term “cyclic deposition process” can refer to avapor deposition process in which deposition cycles, typically aplurality of consecutive deposition cycles, are conducted in a processchamber. Cyclic deposition processes can include cyclic chemical vapordeposition (CVD) and atomic layer deposition processes. A cyclicdeposition process can include one or more cycles that include plasmaactivation of a precursor, a reactant, and/or an inert gas.

As used herein, the term “atomic layer deposition” (ALD) can refer to avapor deposition process in which deposition cycles, typically aplurality of consecutive deposition cycles, are conducted in a processchamber. Typically, during each cycle, the precursor is chemisorbed to adeposition surface (e.g., a substrate surface or a previously-depositedunderlying surface such as material from a previous ALD cycle), forminga monolayer or sub-monolayer that does not readily react with additionalprecursor (i.e., a self-limiting reaction). Thereafter, a reactant(e.g., another precursor or reaction gas/reactant) may subsequently beintroduced into the process chamber for use in converting thechemisorbed precursor to the desired material on the deposition surface.Typically, this reactant is capable of further reaction with theprecursor. Further, purging steps may also be utilized during each cycleto remove any excess precursor from the process chamber and/or removeany excess reactant and/or reaction byproducts from the process chamberafter conversion of the chemisorbed precursor. Further, the term “atomiclayer deposition,” as used herein, is also meant to include processesdesignated by related terms, such as chemical vapor atomic layerdeposition, atomic layer epitaxy (ALE), molecular beam epitaxy (MBE),gas source MBE, or organometallic MBE, and chemical beam epitaxy whenperformed with alternating pulses of precursor composition(s), reactivegas, and purge (e.g., inert carrier) gas. Plasma-enhanced ALD (PEALD)can refer to an ALD process, in which a plasma is applied during one ormore of the ALD steps.

In this disclosure, “continuously” refers to without breaking a vacuum,without interruption as a timeline, without any material interveningstep, without changing treatment conditions, immediately thereafter, asa next step, or without an intervening discrete physical or chemicalstructure between two structures other than the two structures in someembodiments and depending on the context.

A flowability (e.g., an initial flowability) can be determined asfollows:

TABLE 1 bottom/top ratio (B/T) Flowability  0 < B/T < 1 None  1 ≤ B/T <1.5 Poor 1.5 ≤ B/T < 2.5 Good 2.5 ≤ B/T < 3.5 Very good 3.5 ≤ B/T    Extremely goodwhere B/T refers to a ratio of thickness of film deposited at a bottomof a recess to thickness of film deposited on a top surface where therecess is formed, before the recess is filled. Typically, theflowability is evaluated using a wide recess having an aspect ratio ofabout 1 or less, since generally, the higher the aspect ratio of therecess, the higher the B/T ratio becomes. The B/T ratio becomes higherwhen the aspect ratio of the recess is higher. The flowability istypically evaluated when a film is deposited in a wide recess having anaspect ratio of about 1 or less. As used herein, a “flowable” film ormaterial exhibits good or better flowability.

As set forth in more detail below, flowability of film can betemporarily obtained when a volatile hydrocarbon precursor, for example,is polymerized by a plasma and deposited on a surface of a substrate,wherein the gaseous precursor is activated or fragmented by energyprovided by plasma gas discharge, so as to initiate polymerization, andwhen the resultant polymer material is deposited on the surface of thesubstrate, the material shows temporarily flowable behavior. When thedeposition step is complete, the flowable film is no longer flowable butis solidified, and thus, a separate solidification process may not beemployed.

In this disclosure, any two numbers of a variable can constitute aworkable range of the variable, and any ranges indicated may include orexclude the endpoints. Additionally, any values of variables indicated(regardless of whether they are indicated with “about” or not) may referto precise values or approximate values and include equivalents, and mayrefer to average, median, representative, majority, etc. in someembodiments. Further, in this disclosure, the terms “including,”“constituted by” and “having” can refer independently to “typically orbroadly comprising,” “comprising,” “consisting essentially of,” or“consisting of” in some embodiments. In this disclosure, any definedmeanings do not necessarily exclude ordinary and customary meanings insome embodiments.

Turning now to the figures, FIG. 1 illustrates a method 100 of filling arecess on a surface of a substrate in accordance with exemplaryembodiments of the disclosure. FIG. 2 illustrates problems that mayarise during deposition of a carbon layer. FIGS. 3 and 4 illustrateportions of a structure that can form during method 100. FIG. 5illustrates a reactor system in accordance with examples of thedisclosure.

With reference to FIG. 1 , method 100 includes the steps of providing asubstrate within a reaction space (step 102), forming a first carbonlayer (step 104), etching a portion of the first carbon layer within therecess (step 106), and forming a second carbon layer (step 108). Asillustrated, method 100 can also include the steps of etching a portionof the second carbon layer (step 110) and forming a third carbon layer(step 112). As used herein, “first carbon layer” can refer to a carbonlayer that is deposited before step 106; “second carbon layer” can referto one or more intermediate carbon layers that are deposited prior tostep 112. In other words, structures as described herein can includemultiple second carbon layers, which can be formed by repeating steps108 and 110, as shown via loop 114.

During step 102, a substrate is provided into a reaction chamber of areactor. In accordance with examples of the disclosure, the reactionchamber can form part of a cyclical deposition reactor, such as anatomic layer deposition (ALD) (e.g., PEALD) reactor or chemical vapordeposition (CVD) (e.g., PECVD) reactor. Various steps of method 100 canbe performed within a single reaction chamber or can be performed inmultiple reaction chambers, such as reaction chambers of a cluster tool.

During step 102, a substrate can be brought to a desired temperatureand/or the reaction chamber can be brought to a desired pressure, suchas a temperature and/or pressure suitable during step 104. By way ofexamples, a temperature (e.g., of a substrate or a substrate support)within a reaction chamber can be between about 20° C. and about 100° C.,or less than 100° C. A pressure within the reaction chamber can be fromabout 200 Pa to about 1,250 Pa.

FIG. 3(a) schematically illustrates a top portion of a substrate 302having features 304 formed thereon, with gaps 306 formed betweenfeatures 304. As can be appreciated, a surface 308 of substrate 302 andother structures illustrated herein may be exaggerated to illustrateembodiments of the disclosure. Further, as noted above, substrate 302can include additional layers and/or features.

During step 104, a first carbon layer 310, illustrated in FIG. 3(b), isdeposited on the substrate. Exemplary techniques for depositing firstcarbon layer 310 on the substrate surface include cyclical depositionprocesses, such as PECVD, PEALD, or hybrid PECVD/PEALD techniques. Forprocesses including PECVD, a plasma power can be pulsed and/or activatedspecies formed via a plasma can be pulsed to a reaction.

An exemplary cyclic or PEALD process can include the sub steps ofexposing the substrate to a precursor, purging the reaction chamber,expositing the substrate to a reactant (e.g., a plasma-activatedreactant), purging the reaction chamber, and repeating these steps untilan initial desired thickness of the carbon layer is obtained. Atemperature within the reaction chamber and/or of a susceptor can be thesame or similar as the temperature during step 102. Similarly, thepressure within the reaction chamber can be as described above inconnection with step 102. A power applied to electrodes during step 104(e.g., during a reactant or activated reactant pulse) can range fromabout 50 W to about 300 W. A frequency of the power can range from about2.0 MHz to about 27.12 MHz.

Exposing the substrate to a precursor can include providing a precursorrepresented by the formula C_(x)H_(y)N_(z), where x is a natural numbergreater than or equal to 2, y is a natural number, and z is zero or anatural number. For example, x can range from about 2 to about 15, y canrange from about 4 to about 30, and z can range from about 0 to about10. The precursor can include a chain or cyclic molecule having two ormore carbon atoms and one or more hydrogen atoms, such as moleculesrepresented by the formula above. By way of particular examples, theprecursor can be or include one or more aromatic hydrocarbon structures.

A flowrate of the precursor from a precursor source to the reactionchamber can be from about 0.1 slm to about 2.0 slm. A duration of eachexposing the substrate to a precursor sub step can be from about 0.1 secto about 5.0 sec.

The steps of purging the reaction chamber can include flowing an inertgas to the reaction chamber and/or providing a vacuum pressure withinthe reaction chamber. A flowrate of the purge gas to the reactionchamber can be from about 0.1 slm to about 2.0 slm. A duration of eachpurging sub step can be from about 0.1 sec to about 5.0 sec.

The sub step of expositing the substrate to a reactant can includeproviding one or more of an oxygen-containing gas, such as oxygen andN₂O, a hydrogen-containing gas, such as hydrogen, a nitrogen-containinggas, such as nitrogen and N₂O, and/or one or more inert gases, such asargon and/or helium, to the reaction chamber. The reactant may bediluted with a carrier gas, such as nitrogen and/or an inert gas. By wayof examples, the reactant gas can include helium.

A flowrate of the reactant (including any carrier gas) from a reactantsource to the reaction chamber can be from about 0.1 slm to about 4.0slm. A duration of each exposing the substrate to a reactant sub stepcan be from about 0.1 sec to about 0.5 sec.

In accordance with exemplary aspects of the disclosure, an activatedspecies is formed by exposing a reactant gas to radio frequency and/ormicrowave plasma. A direct plasma and/or a remote plasma can be used toform the activated species. In some cases, the reactant can becontinuously flowed to the reaction chamber and the reactant can beperiodically activated for a cyclical deposition process. In thesecases, an on time for the plasma for each cycle can be from about 0.5sec to about 10.0 sec.

Step 104 sub steps can be performed a number of times until a desiredfilm thickness is obtained. Further, subsets of sub steps can berepeated prior to proceeding to the next step.

In the case of cyclic CVD, a reactant and a precursor can be introducedinto the reaction chamber at the same time. The reactants and/orreaction byproducts can be purged as described herein. Further, hybridCVD/PECVD-ALD/PEALD processes can be used, wherein a reactant andprecursor can react in the gas phase for a period of time and whereinsome ALD occurs.

During step 104, the deposited material can initially flow. Thereafter,first carbon layer 310 may become solid.

FIGS. 2 and 3 (b) illustrate structures 200 and 314, respectively, whichcan be formed during step 104. As illustrated, structure 200 can includea void 202 and a wavy surface 204. Similarly, structure 314 includes avoid 312 formed within the as-deposited first carbon layer 310. Withoutfurther treatment, structures 200 and 314 would include the undesirablywavy surface and could include undesirable seams and/or voids.

In accordance with particular examples of the disclosure, as illustratedin FIG. 3(b), first carbon layer 310 can be deposited until first carbonlayer 310 fills recess 306 to at least a top surface 316 of thesubstrate 302. However, unless otherwise stated, this need not be thecase.

During step 106, a portion of the first carbon layer 310 within therecess 306 is etched, as illustrated in FIG. 3(c). In the illustratedcase, a portion of first carbon layer 310 is removed, such that asurface 318 of remaining first carbon layer material 322 within recess306 is below the top surface 316. In the illustrated case, void 312 isopened to form open void 320. This allows open void 320 to be filledusing subsequent steps described below.

During step 106, an etchant is flowed to the reaction chamber. Exemplaryetchants include oxygen-containing gases, such as oxygen, orhydrogen-containing gases, such as hydrogen. In these cases, the gasinclude from about 5.0% to about 50.0% oxygen-containing gas orhydrogen-containing gas in an inert gas. In some cases, the etchant caninclude one or more of oxygen, hydrogen, argon, helium, and nitrogen. Aflowrate of the gas (e.g., oxygen-containing gas and any inert gas) canrange from about 1.0 slm to about 4.0 slm.

Activated species can be formed from the gas (e.g., oxygen-containinggas or hydrogen-containing gas and any inert gas) using a direct and/orremote plasma. A power applied to electrodes during step 106 can rangefrom about 100 W to about 800 W. A frequency of the power can range fromabout 2.0 MHz to about 27.12 MHz.

In accordance with various embodiments of the disclosure, a temperaturewithin the reaction chamber during step 106 is less than 100° C. or isbetween about 20° C. and about 100° C. A pressure within the reactionchamber during step 106 can be from about 200 Pa to about 1,250 Pa.

During step 108, a second carbon layer 324, illustrated in FIG. 3(d), isdeposited overlying substrate 302. Exemplary techniques for depositingsecond carbon layer 324 on the substrate surface include cyclicaldeposition processes, such as PECVD, PEALD, or hybrid PECVD/PEALDtechniques, such as those described above in connection with step 104. Areaction chamber pressure, reaction chamber temperature, and/or plasmapower conditions (e.g., power and frequency) during step 108 can be thesame or similar to those described above in connection with step 104.Similarly, the same or similar precursors and/or reactants can be usedduring step 108 as used during step 104. As illustrated, second carbonlayer 324 can be deposited until a surface 326 of second carbon layer324 is above substrate surface 316. As further illustrated, surface 326may still exhibit an undesirably wavy surface.

During step 110, a portion of the second carbon layer 324 is etched orotherwise removed, as illustrated in FIG. 3(e). In the illustrated case,a portion of second carbon layer 324 is removed, such that a surface 328of remaining second carbon layer material 330 is above top surface 316of substrate 302. Further, step 110 can form a substantially planar(non-wavy) surface 328.

In accordance with various embodiments of the disclosure, a temperaturewithin the reaction chamber during step 108 is less than 100° C. or isbetween about 20° C. and about 100° C. A pressure within the reactionchamber during step 108 can be from about 200 Pa to about 1,250 Pa. Apower applied to electrodes during step 108 can range from about 50 W toabout 300 W. A frequency of the power can range from about 2.0 MHz toabout 27.12 MHz.

As illustrated in FIG. 1 , steps 108 and 110 can be repeated a number oftimes via loop 114 to form structure 332. In some cases, as noted above,at least one instance of step 108 can include depositing the secondcarbon layer until the second layer fills recess 306 to at least topsurface 316. In these cases, at least one occurrence of step 110 caninclude etching a portion of the second carbon layer until a surface ofthe second carbon layer within the recess is below the top surface;however, in other cases, the etch/removal step does not remove thesecond carbon layer to below top surface 316. After the last occurrenceof step 110, remaining second carbon layer material 330 is preferablyabove top surface 316.

With reference to FIG. 1 and FIG. 3(f), during step 112, a third carbonlayer 334 can be deposited over remaining second carbon layer material330. A reaction chamber pressure, reaction chamber temperature, and/orplasma power conditions (e.g., power and frequency) during step 112 canbe the same or similar to those described above in connection with steps104 and 108. Similarly, the same or similar precursors and/or reactantscan be used during step 112 as used during steps 104 and 108.

Each of steps 102-104 or sub steps or any combination thereof can beperformed within the same reaction chamber. Alternatively, multiplereaction chambers—e.g., of the same cluster tool—can be used for one ormore of the steps or sub steps.

Referring again to FIG. 1 , one or more of steps 104, 108, and 112 caninclude a treatment step. The treatment step can include a plasmatreatment step. Exemplary plasma treatment steps can include exposingone or more of the first carbon layer, the second carbon layer, and thethird carbon layer to species formed using one or more of a directplasma and a remote plasma. The species can be formed from one or moreof argon, helium, nitrogen, and hydrogen (e.g., a combination of argonand helium or a combination of nitrogen and hydrogen). A temperaturewithin a reaction chamber during the species formation for treatment canbe less than 100° C. or between about 20° C. and about 100° C. Apressure within a reaction chamber during the species formation fortreatment can be from about 200 Pa to about 1,250 Pa. A power applied toelectrodes during the species formation for treatment can range fromabout 100 W to about 800 W. A frequency of the power can range fromabout 2.0 MHz to about 27.12 MHz. The species formation for treatmentstep can be formed in the same reaction chamber used for one or more orsteps 102-112 or can be a separate reaction chamber, such as anotherreaction chamber of the same cluster tool.

FIG. 4 illustrates scanning transmission electron microscopy imagesafter step 104 (FIG. 4(a)), after step 106 (FIG. 4(b)), and after step108 (FIG. 4(c)). In the illustrated examples, a top surface of thesecond carbon layer is relatively smooth.

FIG. 5 illustrates a reactor system 500 in accordance with exemplaryembodiments of the disclosure. Reactor system 500 can be used to performone or more steps or sub steps as described herein and/or to form one ormore structures or portions thereof as described herein.

Reactor system 500 includes a pair of electrically conductive flat-plateelectrodes 4, 2 in parallel and facing each other in the interior 11(reaction zone) of a reaction chamber 3. A plasma can be excited withinreaction chamber 3 by applying, for example, HRF power (e.g., 13.56 MHzor 27 MHz) from power source 25 to one electrode (e.g., electrode 4) andelectrically grounding the other electrode (e.g., electrode 2). Atemperature regulator is provided in a lower stage 2 (the lowerelectrode), and a temperature of a substrate 1 placed thereon can bekept at a desired temperature. Electrode 4 can serve as a gasdistribution device, such as a shower plate. Reactant gas, dilution gas,if any, precursor gas, and/or etchant can be introduced into reactionchamber 3 using one or more of a gas line 20, a gas line 21, and a gasline 22, respectively, and through the shower plate 4. Althoughillustrated with three gas lines, reactor system 500 can include anysuitable number of gas lines.

In reaction chamber 3, a circular duct 13 with an exhaust line 7 isprovided, through which gas in the interior 11 of the reaction chamber 3can be exhausted. Additionally, a transfer chamber 5, disposed below thereaction chamber 3, is provided with a seal gas line 24 to introduceseal gas into the interior 11 of the reaction chamber 3 via the interior16 (transfer zone) of the transfer chamber 5, wherein a separation plate14 for separating the reaction zone and the transfer zone is provided (agate valve through which a wafer is transferred into or from thetransfer chamber 5 is omitted from this figure). The transfer chamber isalso provided with an exhaust line 6. In some embodiments, thedeposition, etch and/or surface treatment steps are performed in thesame reaction space, so that two or more (e.g., all) of the steps cancontinuously be conducted without exposing the substrate to air or otheroxygen-containing atmosphere.

In some embodiments, continuous flow of a carrier gas to reactionchamber 3 can be accomplished using a flow-pass system (FPS), wherein acarrier gas line is provided with a detour line having a precursorreservoir (bottle), and the main line and the detour line are switched,wherein when only a carrier gas is intended to be fed to a reactionchamber, the detour line is closed, whereas when both the carrier gasand a precursor gas are intended to be fed to the reaction chamber, themain line is closed and the carrier gas flows through the detour lineand flows out from the bottle together with the precursor gas. In thisway, the carrier gas can continuously flow into the reaction chamber,and can carry the precursor gas in pulses by switching between the mainline and the detour line, without substantially fluctuating pressure ofthe reaction chamber.

A skilled artisan will appreciate that the apparatus includes one ormore controller(s) 26 programmed or otherwise configured to cause one ormore method steps as described herein to be conducted. The controller(s)are communicated with the various power sources, heating systems, pumps,robotics and gas flow controllers, or valves of the reactor, as will beappreciated by the skilled artisan.

In some embodiments, a dual chamber reactor (two sections orcompartments for processing wafers disposed close to each other) can beused, wherein a reactant gas and a noble gas can be supplied through ashared line, whereas a precursor gas is supplied through unshared lines.

The example embodiments of the disclosure described above do not limitthe scope of the invention, since these embodiments are merely examplesof the embodiments of the invention. Any equivalent embodiments areintended to be within the scope of this invention. Indeed, variousmodifications of the disclosure, in addition to those shown anddescribed herein, such as alternative useful combinations of theelements described, may become apparent to those skilled in the art fromthe description. Such modifications and embodiments are also intended tofall within the scope of the appended claims.

What is claimed is:
 1. A method of filling a recess on a surface of asubstrate, the method comprising the steps of: providing a substrate ina reaction space of a reactor, the substrate comprising a surfacecomprising a recess; forming a first carbon layer within the recess,wherein the first carbon layer is initially flowable; etching a portionof the first carbon layer within the recess; and forming a second carbonlayer within the recess, wherein the temperature of the reaction chamberduring the step of etching a portion of the first carbon layer isbetween about 20° C. and about 100° C.
 2. The method of claim 1, whereinthe second carbon layer is initially flowable.
 3. The method of claim 2,further comprising a step of etching a portion of the second carbonlayer.
 4. The method of claim 3, further comprising repeating the stepsof forming the second carbon layer and etching the portion of the secondcarbon layer.
 5. The method of claim 3, wherein one or more of the stepsof etching the portion of the first carbon layer and etching the portionof the second carbon layer comprise a plasma-enhanced etch process. 6.The method of claim 5, wherein an etchant used during one or more of thesteps of etching the portion of the first carbon layer and etching theportion of the second carbon layer comprises supplying one or more ofoxygen or hydrogen to the reaction space.
 7. The method of claim 5,wherein the step of etching a portion of the first carbon layercomprises etching the first carbon layer until a surface of the firstcarbon layer within the recess is below the top surface.
 8. The methodof claim 1, further comprising a step of forming a third carbon layeroverlying the second carbon layer.
 9. The method of claim 8, wherein thethird carbon layer is formed using one or more of plasma-enhancedchemical vapor deposition, plasma-enhanced atomic layer deposition, anda hybrid chemical vapor deposition and atomic layer deposition process.10. The method of claim 8, wherein one or more of the steps of formingthe first carbon layer, forming the second carbon layer, and forming thethird carbon layer comprise providing a precursor represented by theformula C_(x)H_(y)N_(z), where x is a natural number greater than orequal to 2, y is a natural number, and z is zero or a natural number.11. The method of claim 10, wherein one or more of the steps of formingthe first carbon layer, forming the second carbon layer, and forming thethird carbon layer further comprise: after providing the precursor,purging the reaction chamber; after purging the reaction chamber,providing a reactant; exposing the reactant to a plasma to form anactivated species from the reactant; and exposing the activated speciesto the substrate.
 12. The method of claim 11, wherein the reactant iscontinuously flowed into the reaction chamber through the steps ofproviding the reactant, exposing the reactant to the plasma, andexposing the activated species to the substrate, and wherein the step ofexposing the reactant to the plasma comprises periodically turning theplasma on and off.
 13. The method of claim 8, wherein one or more of thesteps of forming the first carbon layer, forming the second carbonlayer, and forming the third carbon layer comprise providing a precursorcomprising a chain or cyclic molecule having two or more carbon atomsand one or more hydrogen atoms.
 14. The method of claim 8, wherein atemperature within the reaction space during one or more of the steps offorming the first carbon layer, forming the second carbon layer, andforming the third carbon layer is less than 100° C.
 15. The method ofclaim 8, wherein one or more of the steps of forming the first carbonlayer, forming the second carbon layer, and forming the third carbonlayer comprise a plasma treatment step, wherein the plasma treatmentstep comprises exposing one or more of the first carbon layer, thesecond carbon layer, and the third carbon layer to species formed usingone or more of a direct plasma and a remote plasma.
 16. The method ofclaim 15, wherein the species are formed from one or more of argon,helium, nitrogen, and hydrogen.
 17. The method of claim 16, wherein thetemperature of the reaction chamber during the plasma treatment step isbetween about 20° C. and about 100° C.
 18. The method of claim 1,wherein the first carbon layer fills the recess to at least a topsurface of the substrate.
 19. The method of claim 1, wherein the secondcarbon layer fills the recess to at least a top surface of thesubstrate.
 20. The method of claim 1, wherein the step of etching aportion of the second carbon layer comprises etching the second carbonlayer until a surface of the second carbon layer within the recess isbelow the top surface.
 21. The method of claim 1, wherein the firstcarbon layer and second carbon layer are formed using one or more ofplasma-enhanced chemical vapor deposition, plasma-enhanced atomic layerdeposition, and a hybrid chemical vapor deposition and atomic layerdeposition process.
 22. The method of claim 21, wherein one or more ofplasma-enhanced chemical vapor deposition, plasma-enhanced atomic layerdeposition, and a hybrid chemical vapor deposition and atomic layerdeposition process comprise providing argon or helium dilution gas forigniting and sustaining the plasma.